Other
Scientific paper
Aug 1997
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997natur.388..854l&link_type=abstract
Nature, Volume 388, Issue 6645, pp. 854-857 (1997).
Other
146
Scientific paper
Meteorite chronometry based on the 182Hf-182W system can provide powerful constraints on the timing of planetary accretion and differentiation, although the full potential of this method has yet to be realized. For example, no measurements have been made on the silicate-rich portions of planets and planetesimals other than the Earth and Moon. Here we report tungsten isotope compositions for two eucrites, thought to be derived from asteroid 4 Vesta, and from eight other basaltic achondritic meteorites that are widely considered to be from Mars. The eucrites, which are among the oldest differentiated meteorites, yield exceedingly radiogenic tungsten, indicating rapid accretion, differentiation and core formation on Vesta within the first 5-15 Myr of Solar System history, whereas the range of radiogenic tungsten measurements on the martian meteorites points towards tungsten depletion via melting and core formation within the first 30 Myr of the Solar System. The survival of tungsten isotope heterogeneity in the martian upper mantle implies that no giant impacts or large-scale convective mixing took place since this time. These results contrast with those obtained for the Earth-Moon system, for which accretion and core formation related to giant impacts appears to have continued for at least an additional 20 Myr.
Halliday Alex N.
Lee Der-Chuen
No associations
LandOfFree
Core formation on Mars and differentiated asteroids does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Core formation on Mars and differentiated asteroids, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Core formation on Mars and differentiated asteroids will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-807098